Dental Disease and Diabetes

Dental disease is a wake-up call that your diet is harming your body, concludes Dr. Philippe P. Hujoel. He reviewed the two hypotheses about whether or not dental disease is a warning that we are headed toward chronic system illness. After examining all the evidence, he concludes that it is.

"The five-alarm fire bell of a tooth ache is difficult to ignore," Dr. Hujoel told me. He is professor of dental public health sciences at the University of Washington School of Dentistry in Seattle.

But we do tend to ignore it.

He lays the blame squarely at the feet of Ancel Keys and his believers. Dr. Keys promulgated the lipid hypothesis and focused on excess fat intake as the primary cause of systemic chronic non-communicable diseases -- like diabetes. For Dr. Keys a healthy diet consisted of increasing our intake of "fermentable carbohydrates."

I asked Dr. Hujoel what he meant by fermentable in this context. "Non-fermentable carbohydrates are fibers," he replied. So fermentable carbohydrates are what we usually call available or net carbs.

As a result of the tireless efforts that Dr. Keys made, the medical establishment has come to regard dental diseases as local dietary side effects. The authorities came to view dental diseases as local infections that dentists could treat with fluorides, sealants, oral hygiene, antimicrobials, and dental fillings.

But now clinical trials are putting the opposing dietary hypothesis to the test and are beginning to prove the link between dental and systemic diseases. Dental problems in the short term may in fact portend potentially serious chronic diseases in the long term.

Two physicians, Thomas Cleave and John Yudkin, were the two leading protagonists of the counterargument. Dr. Cleave hypothesized that fermentable carbohydrates such as white flour and white or brown sugar caused many Western diseases, including both dental diseases and diabetes. Dr. Yudkin wrote that sugar causes both dental and chronic non-communicable diseases.

The Journal of Dental Research just published Dr. Hujoel's review of the evidence for and against the dietary link between dental disease and chronic diseases. He calls his review "Dietary Carbohydrates and Dental-Systemic Diseases."

Dr. Hujoel says that for years some medical establishments have told us to make fermentable carbohydrates the foundation of our diet. They say that fats are evil. They assume that we could prevent many systemic chronic diseases by eating a diet high in carbohydrates. Unfortunately, that diet is bad for our dental health and we end up with cavities and gum disease.

But Dr. Hujoel asks whether fermentable carbohydrates are also bad for our systemic health. He explores the close connection between our biology that causes dental problems and those that spike our blood glucose levels. Eating fermentable carbohydrates is now accepted as initiating dental disease.

"Eating these same foods," he says, "is also associated with spikes in blood sugar levels. There is fascinating evidence that suggests that the higher the glycemic level of a food, the more it will drop the acidity of dental plaque and the higher it will raise blood sugar. So, possibly, dental decay may really be a marker for the chronic high-glycemic diets that lead to both dental decay and chronic systemic diseases."

"Dental problems from poor dietary habits appear in a few weeks to a few years," Dr. Hujoel explains. "Dental improvement can be rapid when habits are corrected. For example, reducing sugar intake can often improve gingivitis scores (a measurement of gum disease) in a couple of weeks. Dental disease reveals very early on that eating habits are putting a person at risk for systemic disease. Because chronic medical disease takes decades to become severe enough to be detected in screening tests, dental diseases may provide plenty of lead-time to change harmful eating habits and thereby decrease the risk of developing the other diseases of civilization."

When Dr. Hujoel sent me a draft of his article at the beginning of the year, he told me the background. "My story started November 2007 at the San Antonio airport. I was in the bookstore and saw Gary Taubes's book, Good Calories, Bad Calories. I knew and respected him as a science reporter. I had no interest in diet whatsoever, but decided to buy and read his book nonetheless. At the same time I bought a huge bag of gummy bears and started reading the book on the airplane.

"I have never bought gummy bears since. After 46 years, the book cured me of a lifelong carbohydrate addiction. I loved and still love carbs, but I realize now that my increasing weight problem and maybe my high fasting blood glucose was due to my tremendously high carbohydrate intake. As a dentist, it is absolutely amazing to me that my teeth were rotting away in my jaw and that I never put two and two together."

Dr. Hujoel ended his message with this valediction: "All the best in a low-carb world."

He is a professor and a dentist, while I am just a journalist who has diabetes. But reading Taubes had the same impact on each of us.

You can do a big favor for your body by reading Good Calories, Bad Calories and Dr. Hujoel's new article. The Taubes book is now available in a paperback edition, and the free abstract of Dr. Hujoel's review is available online.